1. Field of the Invention
The present invention relates to a turning behavior display device for displaying controlling conditions of turning behavior of a vehicle having a turning behavior control unit.
2. Description of the Related Art
Various related techniques have hitherto been put forward for enhancing the safety of a vehicle by means of attempting stabilization of a vehicle in course of turning action. For instance, a related technique is to feedback-control a difference between the driving force of left wheels and that of right wheels of a vehicle and brake force exerted on the respective wheels in accordance with a yaw rate of the vehicle, or another related technique is to feedback-control an electronic control LSD (Limited Slip Differential) of a center differential gear which varies the degree of differential limit on front wheels and the degree of differential limit on rear wheels, in accordance with a yaw rate of the vehicle (see; e.g., JP-A-2007-131229).
According to the technique described in JP-A-2007-131229, the degree of differential limit on the front and rear wheels and the torque and brake applied to the right and left wheels of the vehicle by right and left wheel torque generators are controlled in a consolidated manner, by application of yaw rate feedback control. A disclosed technique limited solely to prevention of oversteering is to control differential movement between the front and rear wheels by means of the center differential so as to intensify force of constraint in conjunction with controlling of torque acting on the left and right wheels of the vehicle.
When such turning behavior control unit is put into practice, a driver can ascertain conditions of turning behavior control by means of displaying the amount of control of torque acting on the right and left wheels and the degree of force of constraint (the degree of differential limit). Thus, the traveling performance and safety performance of the vehicle can be effectively utilized.
A technique for displaying; for example, a driving force distribution ratio and the magnitude of torque acting on the left wheels and the magnitude of torque acting on the right wheels, has already been proposed as a related technique for displaying; for example, the amount of control of the torque acting on the left and right wheels and a distribution ratio (the degree of differential limit) of driving force exerted on the front and rear wheels (see; for example, JP-A-11-98603 and JP-UM-B-5-15046 provided below).
A hitherto-proposed related display device displays the intensity of force of constraint based on the driving force distribution ratio is displayed by means of the degree of a display condition (the amount indicated by a scale), and displays the magnitude of torque on the left wheels and the magnitude of torque on the right wheels are displayed by means of the degree of a display condition (the amount indicated by a scale). The driver visually ascertains the force of constraint of the vehicle and the state of torque acting on the right and left wheels by means of the display condition, thereby perceiving control conditions of turning behavior (a turning force status) of the vehicle according to the state of constraining force of the vehicle and the state of torque acting on the right and left wheels.
However, the related display device displays the intensity of the force of constraint based on the driving force distribution ratio, the magnitude of the torque acting on the left wheels, and the magnitude of the torque acting on the right wheels, respectively. When the respective conditions are displayed simultaneously, a display becomes complicated, which deteriorates driver's visibility. For this reason, control conditions of turning behavior (i.e., the turning force status) are estimated by means of a difference between the magnitudes of torques exerted on the right wheels. Therefore, difficulty is encountered in instantaneously ascertaining the control conditions of the turning behavior (the turning force status) of the vehicle. As a result, it may be difficult for the driver to perform driving while accurately ascertaining the conditions of the vehicle. As things stand now, the most of the traveling and safety performance of the vehicle is not effectively utilized.